I am having problems printing on card stock (greeting cards) with an aqueous coating on one side. We have multiliths 1250 and 1650(2nd color t-head) with Kompac dampeners. We are using an AB Dick/Presstek 2340 digital plate maker and their Megapro (Itek) polyester plates. Oil base inks and Itek Mega fountain solution 15-1.
The copy looks washed out on the aqueous coating but the copy is perfect printing on the uncoated side of the stock.
We have had a technician from the ink manufacturer come in and he recommended different fountain solutions and a different formulation ink they make but the results were the same.
Has anyone come across a problem like this and can make some recommendations?
We also use electrostatic paper plates and chemistry for some of our work and have no trouble printing on the aqueous coating.
This leads me to believe it is the chemistry but don't know what I should try.

The coating you are trying to print on has silicone/polymers/waxes etc. which makes for high gloss and rub resistance. Not much compatibility when printing on it. Ink jetting is an alternative but that may prove marginal as well. Try sizing the print area and then print on top of the sizing. That will work. Good Luck. John.